My johnson likes redheads.
yuk yuk yuk.
Okay, I got a johnson controller for my chill box too. It's 100% analog with a simple contact inside and a capillary tube that goes inside the box.
if your unit is like this
, then yes, the "probe" is water tight.
upon further reading I see you have a different unit, not analog. I'd still betcha the probe is water-tight. They design these things for use in a fridge you know